I'd like if a blue can confirm this for me. Do you have the same spawn rate for Shadowy Minions on both 10 + 25 man? If so, is the only difference, that the 25 man minions have higher hp?

Here's my reasoning:

A 25 man (Correct me if im wrong) are generally sending 3-4 people down per totem. That leaves 21-22 people outside that the shadowy minions could potentially target with their Spiritual Grasp. Lets go even further and say theres two groups down on 25 man, and subtract 6-8 people. That still leaves 17-19 potential targets.

Whereas a 10 man can only have 7-8 people on the outside when they send people down to the spirit world. So if you have the same spawn rate, i'm sure you see what the issue is.

So the inherent issue (All based on the confirmation that the spawn rate is the same, and that the only difference is the HP) is that the 10 mans have a higher chance at getting gibbed since there's less people to target with the Spiritual Grasp so that one person can take several spiritual grasp hits all within a second.

So basically i'd just like to know if this is indeed the case, or if 25 mans have a faster spawn rate.

This encounter is definitely one of the more challenging boss fights you can face, and after reading some of your feedback, we wanted to follow up with you about a few things:

The spawn rate of the phased adds on 10-player Heroic mode is slower than 25-player Heroic mode. As a matter of fact, the spawn rate is slower on 10-player Heroic mode than it is on 25-player Normal mode.

We are not currently aware of any non-cosmetic bugs with the Gara'jal encounter. If you feel this is incorrect, please be sure to follow-up with all the details.

It is possible that when many Shadowy Minions are active, there may be a higher likelihood of large bursts of damage on 10-player Heroic mode than there is on 25-player. This is something we're currently evaluating and may adjust, without reducing the overall damage output of the minions.

No hotfixes or changes to this encounter have been applied to the game since Tuesday night. In a general sense, we avoid making significant tuning adjustments to encounters (other than exploit fixes or major bugfixes) until after a raid week has concluded. This is the fairest approach for all players that avoids diminishing any current accomplishments, or exacerbating any current struggles.